Two others tending the property fled and may have weapons, Sheriff Keith Royal said. The two men still at large were described as having dark hair, dark eyes and brown skin.

Investigators from the sheriff's office assisted officers from the United States Bureau of Land Management and the U.S. Citizenship and Immigration Services in the raid, Smith said. The property is owned by the BLM and is on the uphill, east side of Highway 49 near where the Independence Trail crosses the highway.

Agents found 19,138 plants and two firearms, a .357 revolver and a .22 caliber handgun, Smith said.

"Some plants were seven feet tall," he said.

One large, healthy plant can yield two pounds of dried marijuana buds, he said, with a street value of three to four thousand dollars per pound.

Agents found the marijuana plants were freshly watered with a drip irrigation system.

They also found food hanging from trees. It was apparent the suspects had been camping in the garden for some time, Smith said.

The operation was largely successful, despite the suspects' fleeing, Royal said.

"It's difficult to get these people in these operations because they run into the underbrush and they're gone," he said.

Officers from the sheriff's Narcotics Task Force and federal agents spent most of the day Friday harvesting the marijuana.

Increasingly, Mexican drug cartels have been planting marijuana in remote areas of California, guarded by Mexican nationals who sometimes have been forced into the work at gunpoint. Traffickers then use profits from pot sales to finance large methamphetamine laboratories in Mexico and the United States, many in Southern California.

"There was nothing medicinal about this marijuana," Smith said. "It's all for profit, grown by the Mexican drug cartel."